TWO SNP politicians have written to the Metropolitan Police after being told that they had decided not to investigate the “cash for peerages” allegations.

Aberdeen Central MSP Kevin Stewart and Stephen Flynn, MP for Aberdeen South, wrote to Detective Inspector Trevor Normoyle, the operational head of the Special Enquiry Team, after he told them there was “insufficient information” on which to launch a criminal investigation.

However, the pair said they were surprised at the claim, given the amount of information published by openDemocracy and The Sunday Times, following their joint investigation.

READ MORE: 'Why won't they look?': Top lawyer questions Met's dismissal of SNP ‘cash for honours' complaint

That revealed last week how Tory treasurers who donated £3 million to the party seemed to be almost guaranteed a peerage.

All but one of the past 16 treasurers have been offered seats in the Lords, having each given at least £3m.

One former Tory party chairman said: “Once you pay your £3m, you get your peerage.”

Following the report, Stewart and Flynn wrote to Metropolitan Police commissioner, Cressida Dick, asking her to “fully investigate whether any law has been broken”.

In their response to Normoyle, they wrote: “Could you please explain what additional information would be needed in order to justify launching an investigation?”

They said they expected that many people would draw parallels between the latest allegations and those from the cash for peerages scandal investigated in 2006 and 2007.

“In that investigation, the police interviewed 136 people, including the then Prime Minister, Tony Blair, who was interviewed three times, and the Scottish First Minister of the day, Jack McConnell.

“When the decision was made not to bring charges against anyone, there was at least a sense that the matter had been properly investigated.

“Perhaps it may be helpful if you could explain the differences that have meant these more recent allegations have not triggered a similar investigation.

“For example; is there a material difference in the information that was available initially or has there been a change in guidance.”

READ MORE: Demand for fresh investigations into PM and Jacob Rees-Mogg over Tory sleaze

The pair added: “Finally, we note that there has only ever been one person convicted of breaching the Honours (Prevention of Abuses) Act 1925, which was in 1933.

“Would it be at all possible to outline the extent of evidence that would be required to bring forward charges or secure a guilty verdict under this act?”

SNP MP Pete Wishart had also called for the matter to be investigated in a letter to Dick, but he too was told there was not enough evidence.

That prompted barrister Jolyon Maugham, director of Good Law Project, to write on social media that the force’s dismissal seemed “to misunderstand the Met's role”.

He said: “It's not @PeteWishart's job to gather the evidence. He doesn't have power to compel the production of documents and interview witnesses. That's the Met's job.

“So why won't they look?”